Rack mountable computer component power distribution unit and method

ABSTRACT

According to the disclosed embodiments of the invention, there is provided a method of supplying electrical power to a series of upright computer blades mounted side-by-side in a closely spaced configuration, including extending an elongated power distribution unit transversely to the upright blades, and electrically interconnecting the upright blades with a series of electrical connectors arranged side-by-side on one side of the distribution unit. In one embodiment of the invention, a second series of electrical connectors are arranged side-by-side on the opposite side of the body of the power distribution unit.

RELATED APPLICATION

[0001] This application claims priority to the following U.S.provisional applications: Serial No. 60/384,996, titled “Rack MountableComputer Component and Method of Making Same”, filed May 31, 2002;Serial No. 60/384,987, titled “Rack Mountable Computer Component CoolingMethod and Device”, filed May 31, 2002; Serial No. 60/384,986, titled“Rack Mountable Computer Component Fan Cooling Arrangement and Method”,and Serial No. 60/385,005, titled “Rack Mountable Computer ComponentPower Distribution Unit and Method”, which are each hereby incorporatedby reference in their entirety.

[0002] This application relates to the following U.S. non-provisionalpatent applications: Attorney Docket Number 7719-110, titled “RackMountable Computer Component and Method of Making Same,” filed May 28,2003; Attorney Docket Number 7719-111, titled “Rack Mountable ComputerComponent Cooling Method and Device,” filed May 28, 2003; and AttorneyDocket No. 7719-112, titled “Rack Mountable Computer Fan CoolingArrangement and Method;” which are each hereby incorporated by referencein their entirety.

BACKGROUND OF THE INVENTION

[0003] 1. Field of the Invention

[0004] The present invention relates in general to a new and improvedmethod and computer components adapted for rack mounting. It moreparticularly relates to such a method and apparatus for computercomponents adapted to be mounted in a compact configuration.

[0005] 2. Related Art

[0006] There have been a variety of different types and kinds of methodsand systems for mounting computer components. For example, reference maybe made to the following United States patents: U.S. PAT. NO. INVENTORISSUE DATE 4,258,967 Boudreau Mar. 31, 1081 4,879,634 Storrow et al Nov.7, 1989 4,977,532 Borkowicz et al. Dec. 11, 1990 5,010,444 Storrow etal. Apr. 23, 1991 5,216,579 Basara et al. Jun. 1, 1993 5,460,441Hastings et al. Oct. 24, 1995 5,571,256 Good et al. Nov. 5, 19965,684,671 Hobbs et al. Nov. 4, 1997 5,877,938 Hobbs et al. Mar. 2, 19995,896,273 Varghese et al. Apr. 30, 1994 6,025,989 Ayd et al. Feb. 15,2000 6,058,025 Ecker et al. May 2, 2000 6,075,698 Hogan et al. Jun. 13,2000 6,220,456 B1 Jensen et al. Apr. 24, 2001 6,305,556 B1 Mayer Oct.23, 2001 6,315,249 B1 Jensen et al. Nov. 13, 2001 6,325,636 B1 Hipp etal. Dec. 4, 2001 Re. 35,915 Hastings et al. Oct. 6, 1998 Des. 407,358Belanger et al. Mar 30, 1999

[0007] As a result of having available a large number of different typesand kinds of mounting techniques, a standard has been adopted formounting computer components in racks according to a certain modularconfiguration. In this regard, computer components such as computerprocessor units, and the like, are mounted one above the other in acolumn in standard size rack configurations. The standard is referred toas the EIA-310-D Standard, as clarified by the Server Rack Specification(SSI).

[0008] The housing for each computer device must have a certain heightdimensions according to the Standard. The height dimension must be amultiple of a standard unit “U”. Thus, there can be computer componentswhich are 1 “U” (standard unit) high or multiples thereof. Thus, therecan also be standard rack mountable computer components which are 1 U, 2U, 3 U, 4 U and so on.

[0009] Thus, according to the conventional currently-used standard,racks are provided for storage of computer components in tightly spaced,densely packed horizontal dispositions, and each computer componentmounted in the rack is suitably dimensioned in multiples of standardunit U. The racks are movably mounted on casters or the like so thatthey can be readily positioned in, for example, a computer room having atightly controlled air conditioning system to ensure proper cooling ofthe computer equipment.

[0010] It is highly desirable to configure the computer components inthe rack in a compact and highly dense manner for some applications.Thus, it has been important for many applications to position in thecomputer room or other assigned space as many computer components aspossible.

[0011] In order to compactly mount the computer components on the rackin a high density manner, they are closely positioned one above theother in a column. The data and power cables are positioned in a backplane area or space within the rack.

[0012] For cooling purposes, various techniques are employed. Forexample, individual fans have been mounted within the housing of eachcomputer component. The interiors of the housing have been exhausted toa fan exhaust plenum chamber often times constructed within the rack atone side thereof.

[0013] Such conventional rack mounted systems have several drawbacks.The individual fans mounted in each component are expensive, andtime-consuming to replace in case of malfunctions. Also, the back planespace and fan exhaust plenum chamber are wasted space in that theyoccupy spaces which could otherwise be filled with computer components.

[0014] Additionally, in order to assemble the rack mounted system forinstallation at the site, each component must be installed in placewithin the rack, and then the cabling for each unit is routed within therack at its back plane space. Such an operation is time consuming, andtherefore expensive since highly trained personnel are required to dosuch an installation. Furthermore, once installed, in order to replace amalfunctioning computer component, the entire system, or at least asubstantial portion thereof, must be shut down so that themalfunctioning unit can be disassembled, and a replacement unitinstalled and reconnected electrically. This, too, is time consuming andexpensive.

[0015] Therefore, it is highly desirable to compactly mount in a highlydense configuration computer components in a rack mounted system.However, due to the cabling requirements for such a large number ofcomputer components mounted in a single rack, it is difficult to installthe components within the rack due to the cabling requirements and stillhave a very densely packed configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following is a brief description of the drawings:

[0017]FIG. 1 is a pictorial view of a rack-mounted system showing thefront, left side and top thereof, which is constructed in accordancewith an embodiment of the present invention;

[0018]FIG. 2 is a front elevational view of the rack-mounted system ofFIG. 1;

[0019]FIG. 3 is a left side elevational view of the rack-mounted systemof FIG. 1;

[0020]FIG. 4 is a rear elevational view of the rack-mounted system ofFIG. 1;

[0021]FIG. 5 is a right side elevational view of the rack-mounted systemof FIG. 1;

[0022]FIG. 6 is a pictorial view of the rack-mounted system of FIG. 1,showing the rear, right side and top thereof;

[0023]FIG. 7 is a pictorial view of the housing of the rack-mountedsystem of FIG. 1 without various components being mounted forillustration purposes;

[0024]FIG. 8 is a pictorial view of the housing of FIG. 7 illustratingthe process of installation of fan/LAN trays;

[0025]FIG. 9 is an enlarged scale pictorial view of one embodiment of afan/LAN tray for the rack-mounted system of FIG. 1;

[0026]FIG. 10 is a pictorial view of the housing of FIG. 7 with thefan/LAN trays installed;

[0027]FIG. 11 is a pictorial view of the housing of FIG. 7 illustratingthe process of installation of blades;

[0028]FIG. 12 is a fragmentary, enlarged scale front elevational view ofthe rack-mounted system of FIG. 1 illustrating the relative positioningof the fan/LAN trays and the blades;

[0029]FIG. 13 is a diagrammatic, right-side elevational view of therack-mounted system of FIG. 1 illustrating the configuration of theright-side cabling;

[0030]FIG. 14 is a bottom fragmentary pictorial view of the rack-mountedsystem of FIG. 1 illustrating the cabling in the front and right portionof the control bay;

[0031]FIG. 15 is a diagrammatic, left-side elevational view of therack-mounted system of FIG. 1 illustrating the configuration of theleft-side cabling;

[0032]FIG. 16 is a bottom fragmentary pictorial view of the rack-mountedsystem of FIG. 1 illustrating the cabling in the rear and left portionof the control bay;

[0033]FIG. 17 is an enlarged scale, fragmentary pictorial view of oneembodiment of a power distribution unit (PDU) for the rack-mountedsystem of FIG. 1;

[0034]FIG. 18 is a front elevational view of the PDU shown in FIG. 17;

[0035]FIG. 19 is a fragmentary top view of the PDU shown in FIG. 17;

[0036]FIG. 20 is a rear elevational view of the PDU shown in FIG. 17;

[0037]FIG. 21 is a diagrammatic view of the rack-mounted system of FIG.1 illustrating the flow of air therethrough;

[0038]FIG. 22 is a diagrammatic view of another embodiment of arack-mounted system according to the present invention and illustratingthe flow of air therethrough;

[0039]FIG. 23 is a diagrammatic view of yet another embodiment of arack-mounted system according to the present invention and illustratingthe flow of air therethrough;

[0040]FIG. 24 is a diagrammatic view of still another embodiment of arack-mounted system according to the present invention and illustratingthe flow of air therethrough;

[0041]FIG. 25 is an enlarged scale top view of one embodiment of a bladeof the rack-mounted system of FIG. 1; and

[0042]FIG. 26 is a left side elevational view of the blade of FIG. 1.

DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION

[0043] According to the disclosed embodiments of the invention, there isprovided a method of supplying electrical power to a series of uprightcomputer blades mounted side-by-side in a closely spaced configuration,including extending an elongated power distribution unit transversely tothe upright blades, and electrically interconnecting the upright bladeswith a series of electrical connectors arranged side-by-side on one sideof the distribution unit. In one embodiment of the invention, a secondseries of electrical connectors are arranged side-by-side on theopposite side of the body of the power distribution unit.

[0044] According to other embodiments of the invention, each one of thecomputer component blades has a similar cut out portion, and the body ofthe power distribution unit has a complementary cross sectional shapereceived by the cut-away portions of the blades to provide a compactmounting arrangement.

[0045] According to at least one of the disclosed embodiments of thepresent invention, there is provided a power distribution unit whichenables a pair of vertically mounted computer components to be mountedvertically in close proximity to one another in a back-to-backconfiguration. Furthermore, the power distribution unit enables thevertical components to be conveniently slipped into a rack and engageelectrically the power distribution unit.

[0046] General System Description

[0047] Referring now to the drawings, and more particularly to FIGS. 1through 21 and 29 and 30, there is illustrated one embodiment of a rackmounted system 10 according to the disclosed embodiments of the presentinvention. The rack mounted system 10 includes a rack housing 12configured generally as a rectangular box having a plurality of verticalbays 14. The embodiment illustrated in the drawings includes threevertically spaced-apart bays 14.

[0048] Each bay 14 is divided into a front bay portion 16 and a rear bayportion 18 by an intermediate transversely-extending horizontal divider19. The intermediate divider 19 is most clearly illustrated in FIG. 7.The bays 14 are formed in the rack housing 12 in a vertical manner oneabove the other. In a bottom portion of the rack housing 12, a controlbay 21 is provided to house various controlled components, ashereinafter described in greater detail.

[0049] The rack housing 12 further includes a fan/LAN tray slot 23 aboveeach bay 14. Each fan/LAN tray slot is configured to accommodate afan/LAN tray such as tray 27.

[0050] The embodiment illustrated in the drawings provides a control bay21 (FIG. 7) having a bottom opening 25 (FIG. 7) for facilitating airflow to receive vertically moving air flow from a vent opening 26 in afloor 28 and vertically through the system 10 as assisted by the fan/LANtrays. At the top of the rack housing 12, an apertured top panel 26(FIG. 1) is provided to permit venting of the vertically moving air flowfrom the system 10.

[0051] At the top portion of each bay 14, in the intermediate regionbetween the front bay portion 16 and the rear bay portion 18, as bestseen in FIGS. 1, 5, 6 and 8, a power distribution unit (PDU) 29 isprovided to supply electricity to various components mounted in the rackmounted system. Each bay is adapted to accommodate a plurality ofcomputer components in the form of open structure computer components orblades, such as blade 32 (FIG. 1), in each of the front bay portions 16and the rear bay portions 18. In the embodiment illustrated in thefigures, eleven blades may be accommodated in each of the front bay andrear bay portions in a generally upright disposition. Thus, in theillustrated embodiment, the system 10 accommodates 66 computercomponents in a densely compact, closely spaced configuration.

[0052] The bottom control bay 21 is adapted to accommodate variouscontrol components. These control components may include a circuitbreaker junction box 34, as most clearly illustrated in FIG. 6. Thecircuit breaker junction box 34 is electrically connected to each PDU.As shown in FIG. 4, a switch module 36 is also provided in the controlbay 21. The switch module 36 is adapted to control communication betweenthe various blades, such as blade 32, and a network, such as a localarea network, wide area network, or a public network, such as theinternet. Further, the control bay 21 accommodates an air intake fanmodule 38 (FIGS. 1 and 5) for facilitating intake of air through thebottom opening 25 and facilitating vertical air flow through the bladesand the bays 14 and out the apertured top panel 26.

[0053] The embodiment of the rack system 10 illustrated in the figuresincludes four casters 41 for rollably supporting the system on the floor26 (FIG. 5) for easy portability of the rack system 10. Otherembodiments of the rack system according to the present invention may befloor mounted, thereby including legs or skids in place of the castersfor direct mounting to the floor.

[0054] Fan/LAN Tray

[0055] Referring now to FIGS. 8 and 9, the fan/LAN tray 27 and itsinstallation into the rack housing 12 will be described in furtherdetail. FIG. 9 illustrates one embodiment of a fan/LAN tray 27 for usewith the rack system 10 illustrated in the drawings. The fan/LAN tray 27includes eight suitable fans for facilitating vertical air flow.Although the embodiment illustrated in the drawings includes eight fansper tray, any suitable number of fans may be used.

[0056] In accordance with the disclosed embodiments of the presentinvention, the fan tray may also be divided into a plurality of separatetrays or tray portions, each of which can be removed independently sothat the remaining tray portion can continue to function. In thisregard, it is contemplated that the LAN connections may be made in aunit or component separate from the fan tray or tray portions so thatthe tray or tray portion may be removed independently of the LANcomponent. In the front portion of the fan/LAN tray 27, a series of LANconnector ports 45 (FIGS. 1 and 9) is provided. In the embodimentillustrated in FIG. 9, each fan/LAN tray 27 includes 12 LAN connectorports 45, the end one of which may be used for test purposes. While 12LAN connectors are shown in the disclosed embodiment, it should beunderstood that any number of such connectors may be employed for agiven application. Internal wiring leads (not shown) from each LANconnector port 45 extend to one of two signal connectors 47 (FIG. 9) inthe back portion of the fan/LAN tray 27. In one embodiment, each signalconnector 47 is a 50 pin signal connector, and is connected electricallyto the switch module 36. Further, each fan/LAN tray includes a AC powerinlet 49 in the back portion for providing power to the fans. Wheninstalled, power may be supplied to the fans 43 through the AC powerinlet 49 from the PDU 29, as hereinafter described in greater detail.

[0057] For facilitating installation of the fan/LAN tray 27 into thefan/LAN tray slot 23 of the rack housing 12, as shown in FIG. 9, guides52 may be provided on the sides of each fan/LAN tray 27. During theinstallation process, the guides, preferably nylon guides, may engagecorresponding member on the sides of the fan/LAN tray slots 23 to helpsupport the fan/LAN tray. Further, a locking mechanism may be providedin conjunction with the guides 52 for securing the fan/LAN tray 27 intothe fan/LAN tray slot 23 to help support the fan/LAN tray. Onceinstalled, each fan/LAN tray 27 occupies an area directly above eitherthe front bay portion 16 or the rear bay portion 18. Accordingly, afan/LAN tray in the front and a fan/LAN tray in the rear may completelycover each bay 14 level. Thus, as illustrated most clearly in FIG. 10, atotal of 6 fan/LAN trays 27, in addition to the air intake fan module 38may be provided in a three bay level rack mounted system 10 according toone embodiment of the present invention.

[0058] Computer Component Construction

[0059] Referring now to FIGS. 11, 25 and 26, the computer components orblades 32 and their installation into the rack housing 12 will now bedescribed in greater detail. Each blade is provided with a pair ofhandles 54 projecting from the front face of a front panel. The frontpanel extends transversely to a rigid upright support or plate, and isconnected to the front edge of the support in an L-shaped configuration.The handles allow a user to easily manipulate the blade 32 to be graspedby the user to slide the blade into or out of its bay. Each blade 32 mayinclude one or more mother boards 56. In the embodiment illustrated inFIGS. 25 and 26, each blade 32 includes two mother boards 56 a, 56 b.Those skilled in the art will appreciate that the number of motherboards included in each blade 32 may be varied according to design. Themother board may include heat sinks such as heat sinks 58 and 59 forfacilitating the cooling of the mother boards. Embodiments of the heatsinks are disclosed in greater detail in U.S. provisional attorneydocket no. 035,374-2003, filed concurrently herewith. Further, eachmother board is provided with random access memory (RAM) 61. The amountof RAM 61 provided for each mother board may be varied as needed. A pairof power supply 63 a, 63 b may be provided on the blade 32 for supplyingpower to their corresponding mother boards 56 a, 56 b. Similarly, a pairof hard disks 64 a, 64 b may also be provided on the blade 32.

[0060] All of the components are mounted on one side of the rigid plateor support 64, which is adapted to be supported vertically within itsbay. Each blade 32 includes a cut-out corner portion or section 65 inits upper back portion. The cut-out portion 65 is sized to receive andaccommodate the PDU 29 therebetween such that two opposing blades 32 and32 a (as shown in FIG. 26) accommodate the PDU 29 almost completely.Thus, a substantially zero footprint is achieved for the PDU 29. Eachblade 32 is provided with an AC power inlet such as an inlet 67 at ornear the cut-out portion 65. Thus, when the blade 32 is installed intothe rack housing 12, the AC power inlet 67 engages electrically acorresponding AC connector such as a connector 76 (FIG. 17) of the PDU29.

[0061] As most clearly illustrated in FIG. 11, the installation of theblade 32 may be achieved in a fast and efficient manner. The blade 32 issimply slid into either the front bay portion 16 or the rear bay portion18 of a bay 14 of the rack housing 12. Each blade 32 is slid back untilits AC power inlet 67 engages a corresponding AC connector 76 on the PDU29. The intermediate dividers 19 serve as a back stop for the blades 32.Each blade 32 is secured in its slot by four blade screws 69, whichattach the blade 32 to the rack housing 12.

[0062] Once the blade 32 has been mounted onto the rack housing 12, ashort blade/LAN connector cable such as a cable 45 (FIG. 12) or a cable71 (FIG. 1) provides electrical networking connection between the blade32 and a network such as a local area network, wide area network or apublic network such as the internet. In this regard, the mother boardsare each mounted at the front of each blade, and thus access thereto isreadily available at front outlets such as at outlet 73 (FIG. 12). Thus,a data connection can be made from the outlet 73, through a short cable45, an inlet 77 of a PDU 29, which is coupled to the switch module 36.

[0063] Power Distribution Unit.

[0064] Referring now to FIGS. 17 through 20, the power distribution unit29 will now be described in greater detail. Power distribution unit 29supplies electrical power to the series of upright computer componentsor blades rack mounted side-by-side in a closely spaced configuration.As best seen in FIG. 26, each one of the blades such as the blades 32and 32 a have the cut out portion or section 65 in its upper backportion for receiving the PDU 29. In this regard, the cut out portions75 are complementary shaped relative to the cross sectional shape of thePDU 29. The PDU 29 is generally rectangular and cross sectioned, and thecut out corner portions 65 are generally L-shaped to compactly receivethe opposite sides of the PDU 29. Thus, the blades such as the blades 32and 32 a can be plugged into the PDU 29 in a very compact manner withoutthe necessity of having a back plane for receiving individual cables.The PDU 29 supplies power from an external power source, through thecircuit breaker junction box 34, to the various blades 32 and thefan/LAN trays 27. Each PDU 29 includes an elongated PDU body 74, whichpreferably is formed of a two piece, 18 gauge steel chassis. Each of twosides of the PDU body 74 includes a series of female AC connectors 76.In the embodiment illustrated in FIGS. 17 through 20, each side isprovided with 12 female AC electrical connectors 76. The twelveconnectors 76 correspond to eleven blades mounted in the front bayportion 16 and the rear bay portion 18 of each bay 14 and a fan/LAN tray27. The twelfth connector is for an AC power outlet on the front of thefan tray.

[0065] Thus, 12 female AC connectors 76 are provided on each of a frontside and a rear side of the PDU body 74. Each set of twelve female ACconnectors 76 receives power through a pair of power cables 72. In oneembodiment, the power cable 72 is a 15 amp power cable with strainedrelief near its junction with the PDU body 74. As described below, thepower cables 72 are routed to the circuit breaker junction box 34 in thecontrol bay 21. The PDU body 74 may also include a series of mountingstuds 78 for installation of the PDU body 74 to the rack housing 12.

[0066] Referring now to FIGS. 13 through 16, the routing of the variouspower and LAN cables will now be described in detail. As illustratedmost clearly in FIG. 13, the power cables 72 from the PDU's 29 at eachbay level are directed along the right side of the rack housing 12toward the front portion of the rack housing 12 and to the bottom, wherethey are connected electrically to the circuit breaker junction box 34.Thus, in the embodiment illustrated in the drawings, six power cables 72are connected to the circuit breaker junction box 34, since there aretwo from each one of the three PDUs. A set of three cables generallyindicated at 80 are each adapted to be coupled to a suitable source ofAC power to supply power to the system 10.

[0067] As also illustrated in FIG. 13, a set of six LAN cables 81 fromthe fan/LAN trays and PDUs are routed along the rear right side of therack housing 12 to the switch module 36. In the embodiment illustratedin the drawings, two LAN cables 81 extend from each PDU which, in turn,are connected electrically to a pair of fifty pin signal connectors 47.Thus, six such cables 81 are directed along the right side of the rackhousing 12. Similarly, as most clearly shown in FIG. 15, six LAN cables81 extend from the fan/LAN trays 27 and PDUs along the left front sideof the rack housing 12. These six cables 81 are also connected at theirlower ends to the switch module 36.

[0068] Once the rack system 10 is fully assembled with all the fan/LANtrays 27, PDUs 29 and the blades 32 in place, a fully assembled andefficient rack mounted system is provided. In such a system, networkingof the various components provided on the blades 32 is also performedefficiently. In the embodiment illustrated in the drawings, elevenblades are accommodated at each of the front bay portion 16 and the rearbay portion 18 at each bay 14. Thus, in the embodiment illustrated, 66such blades 32 may be accommodated. However, some of the slots may beoccupied by master computer components or blades such as the masterblades indicated at 32 a in FIGS. 4 and 6. In the illustratedembodiment, two master blades 32 a are provided in the bottom of thethree blade bays directly above the switch module 36. The master blades32 a are connected electrically directly to the switch module 36 viahigh speed connections (not shown) such as fiber optic connections. Themaster blades control the switch module 36 to switch communicationbetween the various slave blades 32 and the master blades. Accordingly,64 slave blades may be accommodated by the illustrated embodiment of thesystem. Each of the 64 slave blades may be hot swappable, for example,allowing replacement of the blades 32 without causing the shutting downof the system 10.

[0069] Each fan/LAN tray 27 is provided with twelve LAN connector portssuch as the port 45 (FIG. 1). Eleven of the 12 LAN connector ports 45are adapted to permit communication between the various slave blades 32and the switch module 36. The twelfth LAN connector port 45 allows anexternal user to connect an external device such as a laptop computer tothe network. Further, each fan/LAN tray 27 is provided with a centrallydisposed AC power outlet for connecting such an external device.

[0070] According to the disclosed embodiments of the present invention,and as indicated diagrammatically in FIG. 21, the system 10 illustratedin the figures provides efficient air flow to maintain a cool operatingtemperature for the various components mounted on the blades 32. Airflow is directed from the bottom opening 25 by the air intake fan module38 located in the control bay 21. The air intake fan module 38 directsthe air flow vertically through the various open structure blades 32 ateach bay level 14. The air flow is further facilitated by the fans 43 ineach fan/LAN tray 27 to move the air in its upwardly directed path oftravel. The air flow is directed out of the rack housing 12 through theapertured top panel 26.

[0071]FIGS. 21 through 24 illustrate further embodiments of the presentinvention. As illustrated in FIGS. 21 through 24, the intake and exhaustof the air flow may be varied to accommodate various configurations asto the availability of air supply in the immediate environment. Forexample, in FIG. 22, an air intake fan module 38 a draws air from abottom opening 25 a, similar to that illustrated in the embodiment shownin FIGS. 1 through 21. Air flow is directed vertically with the aid offans 43 a mounted on fan/LAN trays. However, unlike the previouslydescribed embodiment, in the embodiment illustrated in FIG. 22, the airflow is re-directed from a vertical path of travel at right angles to ahorizontal path of travel out of the rack system 10 a towards the rearof the rack housing. An air flow hood 85 a facilitates the rearwardre-direction of the air flow.

[0072]FIG. 23 illustrates yet another embodiment of the rack systemaccording to the present invention. In this embodiment, an air intakefan module 38 b draws air horizontally inwardly through an opening suchas defined by a perforated plate 87 b in the bottom front portion of therack housing. The air flow is then re-directed upwardly with the aid offans 43 b mounted in fan/LAN trays. The air flow is directed verticallyout of the top portion of rack system 10 b.

[0073] In the embodiment illustrated in FIG. 24, an air intake fanmodule 38 c draws air horizontally through an opening such as defined bya perforated plate 87 c in the front bottom portion of the rack housing.The air flow is re-directed vertically through this system with the aidof fans 43 c. The air flow is re-directed at right angles to ahorizontal path of travel out of the rack housing rearwardly at the topof the rack housing. The rearward redirection of the air flow isfacilitated by an airflow hood 85 c. It will be appreciated by thoseskilled in the art that other variations on the intake and exhaust ofthe air flow are possible in accordance with other embodiments of thepresent invention.

[0074] While particular embodiments of the present invention have beendisclosed, it is to be understood that various different modificationsand combinations are possible and are contemplated within the truespirit and scope of the appended claims. There is no intention,therefore, of limitations to the exact abstract and disclosure hereinpresented.

What is claimed is:
 1. A method of supplying electrical power to aseries of upright computer blades mounted side-by-side in a closelyspaced configuration, comprising: extending an elongated powerdistribution unit transversely to the upright blades; electricallyinterconnecting individually the upright blades with a series ofelectrical connectors arranged side-by-side on one side of said powerdistribution unit; and supplying electrical power to the connectors forenergizing the blades.
 2. A method according to claim 1, furtherincluding electrically interconnecting individually a second set ofupright computer blades mounted side-by-side in a closely spacedconfiguration with a second series of electrical connectors arrangedside-by-side on the opposite side of said power distribution unit.
 3. Amethod according to claim 2, further including supplying electricalpower to the second series of electrical connectors for energizing thesecond set of blades
 4. A power distribution unit for supplyingelectrical power to a series of upright computer blades mountedside-by-side in a closely spaced configuration, comprising: a bodyextending transversely to the upright blades; said body having a seriesof electrical connectors arranged side-by-side on one side of the body;means for electrically interconnecting individually the upright bladeswith the electrical connectors; and means for supplying electrical powerto the connectors for energizing the blades.
 5. A power distributionunit according to claim 4, further including means for electricallyinterconnecting individually a second set of upright computer bladesmounted side-by-side in a closely spaced configuration.
 6. A powerdistribution unit according to claim 5, wherein said means forelectrically interconnecting individually includes a second series ofelectrical connectors arranged side-by-side on one side of said body. 7.A power distribution unit according to claim 6, further including meansfor supplying electrical power to said second series of electricalconnectors for energizing the second set of blades.
 8. A powerdistribution unit for supplying electrical power to a series of uprightcomputer blades mounted side-by-side in a closely spaced configuration,comprising: an elongated body having a series of electrical connectorsarranged side-by-side on one side of said body; mounting studs formounting said body in a transverse manner relative to said uprightcomputer components to enable each one of the blades to be connectedelectrically with said electrical connectors; and a cable for supplyingelectrical power to said connectors.
 9. A power distribution unitaccording to claim 8, wherein said blades each have a similar cut outportion, said body having a complementary cross sectional shape receivedby the cut-away portions of the blades to provide a compact mountingarrangement.
 10. A power distribution unit according to claim 9, furtherincluding a second series of electrical connectors arranged side-by-sideon the opposite side of said body.
 11. A power distribution unitaccording to claim 10, further including a second cable for supplyingelectrical power to said second series of electrical connectors forenergizing the second set of blades.
 12. A power distribution unitaccording to claim 10, wherein each one of said second set of blades hasa similar cut out portion, said body having a complementary crosssectional shape received by the cut out portions of the second set ofblades to enable the first-mentioned and second sets of blades to bemounted back-to-back in a compact configuration.